Patiets who are unable to produce sputum(a mixture of saliva and mucus coughed up from the respiratory tract, typically as a result of infection or other disease and often examined microscopically to aid medical diagnosis) for examination, an aerosol may be used to increase the flow of secretions and stimulate coughing. Specimens collected for bacteriologic culture must be placed in a sterile container and handled with care to avoid contamination from sources other than the sputum.